what is a good discusssion?

a good discussion does not mean it should be of having 1000 response. in my point of view following things are more imp:
1 the subject must be very good.
2 there must be a healthy discussion
3every one could say the real emotions
4it should point out both pro n con of the subject
5it should not hurt any individual sentiments
6last but not the least many people should put there response